Scientists develop a cheap, smartphone-based test for Zika
Many a world traveler questioned their tropical vacation plans last year after the mosquito-borne Zika virus started making headlines. To test for the disease, which has been tied to a surge of microcephaly cases in infants, physicians look for flu-like symptoms and your recent travel history. They then confirm a diagnosis by testing a blood or urine sample. For modern Western travelers, that’s no big deal. But what about those who may not be able to afford a doctor’s lab tests or clinics unable to afford costly testing equipment in the first place?
Researchers at Sandia National Labs have come up with a diagnostic test for Zika that’s smaller and cheaper than current testing equipment. In fact, it’s based around a smartphone. Like existing tests, it hinges on a blood sample, but then the blood is put through a process called loop-mediated isothermal amplification (LAMP). In this process, a sample mixed with “a few carefully designed biochemical agents” is heated to 150 degrees Fahrenheit for 30 minutes. Any positive DNA fragments in the sample will glow, tagged by a light emitting fluorophore molecule. To check for those positive, glowing reactions, your smartphone (situated over the LAMP box) performs some image recognition using its camera and a dedicated app.
This technique is leagues cheaper than current testing solutions, whose equipment can cost upwards of $20,000. That equipment also tends to be quite large, which, while appropriate for laboratories, isn’t ideal for small clinics. A prototype of this LAMP box, by contrast, can be held in one hand. It’s also faster, with the process only taking half an hour.
“There are billions of smartphones in the world, even in developing countries, and this tool doesn’t require the highest-end smartphone on the market,” chemical engineer and paper lead author Aashish Priye said. “It only needs to have an optical sensor and be able to run the app.”
This solution is just one of a growing number of lab tests and medical diagnostic tools that are moving to the smartphone. For example, in 2014, researchers at the University of Cambridge developed an app that paired with testing strips to monitor a variety of medical conditions. And in 2015, Columbia University researchers developed a mobile-based lab-on-a-chip that could check for HIV and syphilis in only 15 minutes—and cost only $34. Armed with a suite of relatively cheap accessories, physicians working in remote locations could perform a variety of useful, accurate tests minus the lab (and with a fraction of the legwork).
In this case, the app and LAMP box could be used to check not only for Zika but also dengue and chikungunya. These diseases are all spread by the same type of mosquito and result in similar symptoms. Outfitted with these types of tools, clinicians will hopefully be able to identify and treat pandemic threats more quickly and more successfully in the near future.
Source: The Daily Dot
This from Daniel Chang of the Miami Herald.
Florida health officials on Monday reported one more locally acquired Zika infection in a person who felt no symptoms but who was tested for the virus in February.
The person likely acquired Zika in Miami-Dade in 2016 after “multiple exposures” to areas where mosquitoes were spreading the virus, the Florida Department of Health reported, adding that the state had just received confirmation from the federal Centers for Disease Control and Prevention.
In addition, Florida reported four new travel-related Zika infections, raising the total number of cases for 2017 to 29 people, including one locally acquired case from Miami-Dade. Among the 29 cases reported in Florida this year are 13 pregnant women and two people whose source of infection is undetermined after a health department investigation.
Pregnant women are considered to be at the greatest risk from Zika because the virus has been shown to cause microcephaly and other neurological disorders in children born to mothers infected while pregnant. The frequency of Zika infections in Florida has declined over the winter, but public health experts expect the virus to resurface as the temperature warms and rain increases.
Source: Miami Herald
Sperm donated in three Florida counties since June 15 may be infected with the Zika virus, the United States Centers for Disease Control and Prevention cautioned Monday.
“When semen is donated it can be stored frozen for periods of time. It does not necessarily inactivate Zika, so it could be stored in tissue banks, used subsequently and people should be made aware,” said Dr. Peter Marks, director of the Center for Biologics Evaluation and Research at the US Food and Drug Administration. He went on to say having this information can help individuals make informed decisions and they “might want to use these donations from other sources.”
Sources other than the 12 sperm banks in Miami-Dade, Palm Beach and Broward counties of Florida, that is.
The agency had previously designated only Miami-Dade County as an area to take precautions after the first local transmission of the virus in the continental United States was confirmed in the Wynwood neighborhood of Miami in July. The area was declared Zika free in December.
However, the CDC is now warning anyone in Palm Beach and Broward counties to also consider themselves at an increased risk for the virus. This applies to anyone who has traveled to or between these three counties since June 15, 2016, a change from previous guidance that designated June 29 as the start of the increased risk period.
It is possible that someone could have Zika without knowing, because an estimated 80% of those infected have no symptoms. When symptoms occur, they can include fever, rash, joint pain and red eyes, and they can last from a few days to about a week.
Pregnant women are at greatest risk because they can unknowingly pass the virus to their fetus, causing devastating consequences including miscarriage and neurological deficits that last a lifetime.
Because the virus can also be sexually transmitted, pregnant women or those trying to become pregnant have been advised to avoid unprotected sex with a partner who has been infected or who has lived in or traveled to an area where the virus is circulating.
The ongoing investigation into reported cases of the virus in Florida has found that residents of Miami-Dade, Palm Beach and Broward counties travel frequently between the counties and either forget, or fail to, consider that they’ve visited an area of increased risk, thus not realizing they could be infected.
Women who live in these three counties who have become pregnant since June 15 are advised to speak with their physicians about the potential increased risk as are women who want to use a sperm donation from a donor in these counties, advised Dr. Denise Jamieson, incident commander for the CDC Zika emergency response and chief of the women’s health and fertility branch at the CDC’s division of reproductive health.
CDC officials said they are acting only out of an abundance of caution and there have not been any reports of the virus being transmitted through donated sperm.
“Now we understand more than we did months ago is that evidence of the Zika virus is present in semen for up to three months after a man is infected and people may not have accurately recalled potential exposure [to the virus] especially if in a local area,” said Dr. Matthew Kuehnert, who is part of the CDC Zika emergency response team and director of the CDC office of blood, organ and other tissue safety.
Unlike blood donations, which are routinely screened for the virus in the United States, there is no available test to screen semen for Zika. The existing test is still in the research phase and accuracy is being assessed, which is why men in these counties should not donate sperm. Their donated sperm may be infected.
The Florida Department of Health last reported a case of local transmission of the virus on March 2. However, that report included confirmation of two cases from October of last year. A third case was also reported then but this was an individual who donated blood in January and through routine blood screening was found to have previously been infected but no longer had an active case of the virus.
The CDC media statement
Florida health officials confirmed three new locally acquired cases of the Zika virus in Miami-Dade County on Thursday but said they will not lead to any new Zika zones in the city or nearby South Beach.
“Two are cases that had samples collected in October as part of our ongoing investigation and the department just received confirmatory testing back from CDC.,” according to the Florida Department of Health, which added that both cases have been added to 2016 data.
“The third case reported no symptoms, but screening conducted after blood donation in January showed evidence of a past infection,” officials added on Thursday.
“This individual had multiple exposures in Miami-Dade County and likely contracted Zika in 2016,” health officials explained. “Because the individual was asymptomatic, it is difficult to determine when infection occurred. Since the first positive sample was collected in January, this is considered our first locally reported case of Zika in 2017.”
State health officials, however stressed that Florida still does not have any identified areas with ongoing, active Zika transmission.
With the two new cases, the total number of Zika cases reported in Florida for 2016 stands at 1,384. So far in 2017, the total of Zika cases reported in Florida is 18.
Gov. Rick Scott announced on Dec. 9 that the final remaining Zika zone in the state had been lifted — an area of about 1.5 square miles between Eighth and 28th streets in South Beach.
“We will continue to see travelers bringing Zika infections into our state and so we must remain on alert and continue all the protective efforts that we’ve doing that have led to this success,” cautioned Philip, who also serves as Florida’s surgeon general. “That means continuing to use repellent, keeping your skin covered as much as possible …. And we cannot forget about the risk associated with sexual transmission.”
On December 2, 2016, the governor announced that the Little River zone in Miami had been cleared. That area included a one-square-mile stretch between NW 79th Street to the north, NW 63rd Street to the south, NW 10th Avenue to the west and N. Miami Avenue to the east.
In November, Scott gave the all clear to the Miami Beach area north of 28th Street to 63rd Street. Before that, he announced that the Wynwood area of Miami had also seen no new transmissions of Zika. This included the area of Northwest 5th Avenue to the west, U.S. 1 to the East, 38th Street to the north, and 20th Street to the south.
Despite Zika concerns, Florida set a tourism record last year with 112.8 million visitors.
Emergency Preparedness Leaders, National and Local Vector Control Officials, Healthcare Providers, Public and Private Sector Partners and Zika Virus Experts will once again gather to learn findings and solutions about the Zika virus from each other. This is all geared towards the improvement of their preparedness and response efforts in the event of a Zika virus outbreak.
The 2nd International Zika Virus Conference and Workshop once again provides experts, leaders from all government levels (tribal, local, state, federal), and other health officials a venue where they could share the best practices and the latest researches about the Zika virus to delegates coming from different parts of the world. Priority will be placed on identifying the responsibilities of stakeholders in order to improve global communication coordination and collaboration. The ZIKV conference will be held at the Hilton Washington Dulles Airport Hotel on March 29-30 followed by an all-day hands-on workshop on the 31st.
The 2nd iZIKVc will focus on the latest preventions, preparedness, responses and recovery measures being developed to address the transmission of Zika virus. The speakers and exhibitors are selected to present the widest possible range of perspectives—not only human but also physical, environmental, and social-cultural.
Speakers of the event include:
• Zachary S. Thompson
• Dr. Oscar Alleyne
• Dr. Lorrin Pang
• Dr. William N. May
• Phillip Goodman
• Phil Maytubby
• Vincent Cantu
Each day, the conference will offer papers on a wide range of topics including:
• Preparing Community Strategies
• Local Partnership and Participation
• Emergency Response and Hospital/Healthcare Coordination
• Prevention Education Efforts and Risk Communication
Panel discussions include:
• Mosquito Vector Surveillance and Control
• Health Department Response
• Zika Prevention, Community Engagement and Cultural Equity
• Community Strategies/Partnership
• Establishment and Implementation of a Scalable Vector-Borne Disease Response Plan at the Local Level
• Mosquito Response/State Level
• Defending Susceptible Communities from Spread of Arboviruses
• Mitigating Public Health Vulnerabilities
Click here for a free copy of the event brochure.
Scientists have found a way to sterilize mosquitoes that spread Zika virus and dengue fever, and thus to be able to control the insect population, according to research at Yale and Vanderbilt universities
According to a Yale press release, fertilization by infected male insects containing the common bacterium Wolbachia will fail unless the female also is infected with Wolbachia.
“Females inseminated by these males only lay dead (sterile) eggs,” said John Beckmann, a postdoctoral researcher in Yale’s Department of Molecular Biophysics and Biochemistry, in a press release. Beckmann is lead author of a paper in Nature Microbiology and contributing author of a related paper in the journal Nature. “If the sterilized males are released into problem areas we can eliminate insect populations.”
Zika, which causes severe birth defects, and dengue fever, which causes flu-like symptoms and occasionally leads to death, are spread by the Aedes aegypti mosquito. However, that mosquito does not naturally carry Wolbachia, the release said.
By inserting the genes from Wolbachia into males of the Aedes aegypti species, the mosquito population could be controlled, said Mark Hochstrasser, professor of molecular biophysics and biochemistry and of molecular, cellular and developmental biology, in the release. Hochstrasser is senior author of the Nature Microbiology paper.
Beckmann told the New Haven Register that each female can lay 600 eggs in two batches during her life cycle. If she is impregnated by a sterile male, within three generations, there would be millions of sterile mosquitoes, he said.
Yale’s Judith Ronau, a postdoctoral associate in molecular biophysics and biochemistry, is co-lead author of the Nature Microbiology paper. Vanderbilt’s Seth Bordenstein is senior author of the Nature study.
Source: New Haven Register
Scientists with Wayne State University say they are the first to publish research to show the Zika virus can damage retina cells in the eyes, and in some cases cause blindness.
“The key message of the study is that indeed the Zika virus can cause damage,” said Dr. Ashok Kumar, microbiologist and assistant ophthalmology professor with Wayne State University School of Medicine at the Kresge Eye Institute.
Dr. Kumar led a team which launched research in July to publish their study in JCI Insight, the Journal of Clinical Investigation Feb. 23.
Using mice Dr. Kumar says the Zika virus can infect and cause lesions in retina cells, causing damage and in some cases cause blindness. Their research showed the Zika virus mostly killed cells specifically lining the blood-retinal barrier, the retinal endothelium, and retinal pigment epithelium.
“Zika virus can actually infect those cells, and we did … studies and we found it can replicate in those cell types and ultimately it kills those cells,” said Dr. Kumar.
Their study builds on existing research published May 2016 in the Journal of the American Medical Association Ophthalmology that linked the Zika virus to eye problems. Researchers showed that some infants born with congenital Zika infection and microcephaly-or significantly smaller head and underdeveloped brain-in the northeast state of Brazil, Bahia, they also had problems in their retinas, other organs, and some hearing loss.
“Pretty much the whole eye can be infected with the Zika virus,” said Dr. Gary Abrams, ophthalmology professor with Wayne State University School of Medicine at the Kresge Eye Institute, who assisted Dr. Kumar with the clinical aspect of this study.
Dr. Abrams says about one third of infants born with Zika will develop eye issues they have discovered, whereas 15 percent of adults with Zika will have some sort of ocular impact, but most do not get a retinal infection.
“This is a virus that’s fairly pervasive: once the infection occurs it can be pretty much all over the body, including in the eyes, in the tears, and elsewhere,” said Dr. Abrams.
Currently, Dr. Kumar says they are continuing research in hopes of developing methods to track and treat Zika infections. According to the Centers for Disease Control and Prevention, there is no known treatment at this time.
“There are so many questions we don’t know,” said Dr. Kumar. “First thing is: how does the virus replicate? How long is it going to replicate? And what will be the visual outcome.”
“The big question really is that Zika virus was discovered in 1947, so it’s about 70 years, and why suddenly is it becoming so prevalent?”
Source: FOX 17 West Michigan
This just in from Daniel Chang from the Miami Herald.
The Aedes aegypti species of mosquito is believed to be the most capable transmitter of Zika. But University of Georgia ecologists have created a predictive model that suggests up to 35 species of mosquitoes can spread the virus, according to a study published Tuesday in the journal, eLife. Miami-Dade was the only county in Florida to have designated active Zika transmission zones during an outbreak in 2016, according to state health officials.
Zika may be spread by as many as 35 species of mosquitoes, including seven found in the United States, according to a forecasting model created by University of Georgia ecologists and published Tuesday in the journal eLife.
Most scientists, including those at the Centers for Disease Control and Prevention, believe Zika is primarily spread through the bite of an infected Aedes aegypti or Aedes albopictus species of mosquito, both of which are prevalent in Florida.
But University of Georgia ecologists suspect that there must be other types of mosquitoes capable of spreading Zika because an outbreak of the virus on Yap Island in 2007 was driven by a different species, Aedes hensilli — and because other viruses closely related to Zika are spread by more than nine mosquito species, on average.
The Georgia researchers created a model to test their theory, and using mathematical analysis, predicted that 35 species of mosquitoes may be able to spread Zika. Seven of those mosquito species are found in the United States.
University of Georgia researchers recommended their findings be used to prioritize mosquito species for further studies that would confirm their ability to spread Zika while the virus is still laying low.
Zika spread rapidly through Brazil and the Caribbean in 2015 and 2016, leading to a spike in babies with severe birth defects born to mothers infected with Zika while pregnant. Miami became the first city in the United States to have active spread of Zika by mosquitoes last summer, after months of people with travel-related infections were reported in the state.
But despite being named a public health emergency by the World Health Organization and by Florida health officials in February 2016, Zika remained little understood by scientists — including the science of how it spreads, University of Georgia researchers reported.
So far in 2017, Florida has reported four travel-related cases and no new local infections. In 2016, Florida’s health department reported a total of 1,325 Zika cases.
Source: Miami Herald